The effects of ${eta}$-glucan isolated from Aureobasidium pullulans were observed on acute xyleneinduced inflammation. ${eta}$-glucan at a dose of 62.5, 125 or 250 mg/kg were administered once orally to xylene-treated mice (0.03 mL of xylene was applied on the anterior surface of the right ear to induce inflammation), and the body weight change, ear weight, histological profiles and histomorphometrical analyses of ear were conducted upon sacrifce. The xylene was topically applied 30min after dosing with ${eta}$-glucan. The results were compared to those of diclofenac, indomethacin and dexamethasone ( 15 mg/kg injected once intraperitoneally). All animals were sacrificed 2 h after xylene application. Xylene application resulted in marked increases in induced ear weights compared to that of intact control ear; hence, the differences between intact and induced ear were also signifcantly increased. The histological characteristics of acute inflammation, such as severe vasodilation, edematous charges of skin and infiltration of inflammatory cells, were detected in xylene-treated control ears with marked increase in the thickness of the ear tissues. However, these xylene-induced acute inflammatory changes were significantly and dose-dependently decreased by ${eta}$-glucan treatment. We conclude that ${eta}$-glu-can from A. pullulans has a somewhat favorable effect in the reduction of the acute inflamma-tory responses induced by xylene application in mice.